This document provides an introduction to KVM (Kernel-based Virtual Machine), an open source hypervisor that allows running multiple operating systems on a single computer. KVM is integrated into the Linux kernel since version 2.6.20 and provides full virtualization capabilities. It supports hardware virtualization features, sound, snapshots, PCI passthrough, live migration, and more through a layered model. KVM can be managed through tools like Libvirt, Virsh, and Ovirt and is well-suited for cloud computing due to its security, speed, scalability, and reliability.